Is It Safe To Sleep With Contacts In For One Night Or Does It Always Risk Infection

Sleeping in contact lenses, even just once, is a common habit among wearers—especially after a long day or an unexpected nap. While it might seem harmless, ophthalmologists consistently warn against it. The human eye needs oxygen to stay healthy, and contact lenses reduce the amount of oxygen reaching the cornea. When you close your eyes during sleep, that oxygen flow drops further. Combine these two factors, and you create a breeding ground for complications ranging from mild irritation to severe infections.

Despite the convenience, sleeping in contacts—even for a single night—significantly increases the risk of microbial keratitis, a potentially sight-threatening corneal infection. Studies show that individuals who sleep in their contacts are up to six times more likely to develop serious eye infections than those who remove them nightly. This article breaks down the science behind the risks, outlines what can go wrong, and provides practical guidance for minimizing harm if you’ve already dozed off with lenses in.

The Science Behind Oxygen Deprivation and Corneal Health

The cornea—the clear front surface of the eye—has no blood vessels and relies on oxygen from the air to function properly. Contact lenses, especially soft ones, act as a barrier between the cornea and the atmosphere. During waking hours, blinking helps circulate tears and maintain some oxygen flow. But when you sleep, blinking stops, tear exchange diminishes, and oxygen levels in the cornea can drop by 50% or more.

Prolonged oxygen deprivation leads to a condition called hypoxia. In response, the body may initiate neovascularization—the growth of new blood vessels into the cornea to compensate for low oxygen. While this sounds adaptive, it actually compromises vision clarity and increases the risk of scarring and inflammation.

Additionally, closed eyelids trap warmth and moisture, creating an ideal environment for bacteria like Pseudomonas aeruginosa and Staphylococcus aureus to multiply. If microtears exist on the corneal surface (which can occur from lens friction), bacteria can invade and cause infection.

Tip: Even \"extended-wear\" lenses approved for overnight use should be removed regularly as directed by your eye doctor. No contact lens is completely risk-free during sleep.

Types of Contacts and Their Risk Profiles

Not all contact lenses are created equal. Some are FDA-approved for extended or continuous wear, meaning they’re designed to allow higher oxygen permeability. However, approval doesn’t equate to safety for everyone.

Type of Lens	Oxygen Permeability (Dk/t)	Approved for Overnight Wear?	Risk Level (When Slept In)
Traditional Soft Lenses (e.g., hydrogel)	Low to moderate (8–30)	No	High
Silicone Hydrogel Lenses	High (80–175)	Some models yes	Moderate (if approved)
Rigid Gas Permeable (RGP) Lenses	Very high	Rarely recommended	Moderate to High (due to mechanical friction)
Extended-Wear Disposable Lenses	High	Yes (up to 6 nights)	Low to Moderate (with strict hygiene)

Even with high-oxygen lenses, individual factors such as dry eye, immune status, and lens hygiene play critical roles in determining actual risk. A lens approved for six nights of continuous wear still carries a cumulative infection risk of approximately 1 in 500 wearers per year—far higher than daily disposable users who never sleep in their lenses.

“Sleeping in contacts, even occasionally, turns a low-risk activity into a high-stakes gamble with your vision. The cornea doesn’t get second chances.” — Dr. Lena Patel, Corneal Specialist at Boston Eye Institute

What Can Go Wrong: Short-Term and Long-Term Risks

While some people report “getting away with” sleeping in their contacts without immediate issues, the absence of symptoms doesn’t mean there’s no damage. Here’s what can happen—immediately or over time:

• Corneal Edema: Swelling of the cornea due to fluid buildup from hypoxia. Symptoms include blurred vision, halos around lights, and discomfort upon waking.
• Superior Epithelial Arcuate Lesions (SEALs): Micro-abrasions caused by lens edge friction during sleep, increasing infection vulnerability.
• Microbial Keratitis: A serious infection of the cornea. Symptoms include redness, pain, light sensitivity, discharge, and vision loss. Requires urgent medical treatment and can lead to permanent scarring.
• Giant Papillary Conjunctivitis (GPC): An inflammatory response often triggered by protein buildup on lenses worn too long. Causes itching, mucus discharge, and contact lens intolerance.
• Corneal Neovascularization: Long-term oxygen deprivation prompts blood vessel growth into the cornea, which can impair vision and disqualify patients from future refractive surgery.

A 2021 study published in Cornea found that 73% of microbial keratitis cases in contact lens wearers were linked to overnight lens use, even if infrequent. Shockingly, many patients reported only having slept in their lenses “once or twice.”

Mini Case Study: A Single Night Turned Serious

Emily, a 26-year-old graphic designer, wore her standard two-week silicone hydrogel lenses for 14 hours before falling asleep fully clothed after a late-night work session. She woke up 10 hours later with intense pain in her right eye, photophobia, and a sensation of something stuck under her eyelid. By afternoon, her eye was bloodshot and producing pus.

She visited an urgent eye clinic, where doctors diagnosed her with bacterial keratitis. Cultures grew Pseudomonas aeruginosa, a fast-moving pathogen known for destroying corneal tissue rapidly. Emily required intensive antibiotic eye drops every hour, missed two weeks of work, and was told she now has a permanent corneal scar affecting night vision. Her doctor emphasized: “This likely wouldn’t have happened if you’d taken your lenses out that night.”

Step-by-Step Guide: What to Do If You Accidentally Sleep in Your Contacts

If you’ve woken up with contacts still in, don’t panic—but act quickly. Follow this timeline to minimize damage:

1. Do not rub your eyes. Rubbing can worsen micro-abrasions or introduce bacteria.
2. Blink frequently to stimulate tear production and rehydrate the lens and cornea.
3. Apply rewetting drops (preservative-free if possible) to loosen the lens.
4. Gently remove the lens once it moves freely. If it feels stuck, wait a few minutes and try again.
5. Inspect your eyes in the mirror for redness, swelling, or discharge.
6. Do not reuse the lens. Discard it immediately, even if it’s reusable.
7. Wear glasses for the rest of the day to allow your eyes to recover.
8. Monitor for symptoms over the next 24–48 hours: pain, blurred vision, light sensitivity, or persistent redness.
9. Contact your eye doctor immediately if any warning signs appear.

Tip: Keep a pair of glasses and a lens case on your nightstand. This makes removal easier when you're tired.

Best Practices: How to Prevent Accidental Overnight Wear

Prevention is far safer than managing consequences. Consider these strategies to eliminate the temptation or oversight of sleeping in contacts:

• Switch to daily disposables. With no cleaning or storage involved, there’s less incentive to leave them in overnight.
• Create a bedtime routine anchor. Link lens removal to another consistent habit, like brushing your teeth.
• Use a reminder app. Set a nightly alert labeled “Remove Contacts” until the habit becomes automatic.
• Keep your lens case in a visible spot, such as your bathroom counter, not hidden in a drawer.
• Invest in overnight-approved lenses only if medically necessary and under strict supervision from your optometrist.

Checklist: Safe Contact Lens Habits

• ✅ Remove lenses before sleeping—no exceptions
• ✅ Wash and dry hands before handling lenses
• ✅ Replace lens case every 3 months
• ✅ Never top off old solution with new
• ✅ Avoid water exposure (showers, pools, hot tubs)
• ✅ Attend annual eye exams
• ✅ Replace lenses according to schedule (daily, biweekly, monthly)
• ✅ Carry backup glasses or a travel case

Frequently Asked Questions

Can I sleep in my contacts just once without causing harm?

While some people do so without immediate issues, it still poses a measurable risk. Even one night can lead to corneal swelling, micro-abrasions, or bacterial colonization. There is no “safe” threshold—each incident increases cumulative risk. It’s comparable to driving drunk once: you might not crash, but the danger is real and avoidable.

Are extended-wear contacts completely safe for sleeping?

They are safer, not safe. Silicone hydrogel extended-wear lenses allow more oxygen and are FDA-approved for overnight use, but they still carry a higher infection risk than daily wear lenses. They are typically prescribed for specific situations (e.g., shift workers, medical needs) and require closer monitoring. Even then, most eye doctors recommend removing them weekly for cleaning and corneal recovery.

What should I do if my eye hurts after sleeping in contacts?

Remove the lens immediately and switch to glasses. Use preservative-free artificial tears to soothe irritation. If pain, redness, light sensitivity, or blurred vision persists beyond a few hours, seek emergency eye care. Delaying treatment for infections like microbial keratitis can result in permanent vision loss.

Conclusion: Protect Your Vision—One Night Matters

Sleeping in contact lenses, even once, disrupts the delicate balance of ocular health. The temporary convenience is vastly outweighed by the potential for infection, inflammation, and irreversible damage. Your eyes don’t need much—they need consistency. Removing your lenses every night isn’t just a recommendation; it’s a non-negotiable part of responsible vision care.

Whether you’ve done it once or make it a habit, now is the time to change. Implement simple routines, leverage tools like daily disposables or phone reminders, and prioritize your long-term eye health. Your future self—and your vision—will thank you.

💬 Your eyes are irreplaceable. Share this article to help someone avoid a preventable mistake—or leave a comment about your own experience with contact lens safety.